Moscow Polytech has developed an innovative nozzle for chemical industry
Moscow Polytech's researchers presented a new design of a regular nozzle for column devices, which may significantly increase the efficiency of the processes in chemical and petrochemical industry. Low hydraulic resistance and increased firmness to contamination on the surface distinguish the development. Its use has the potential to improve production efficiency, reduce energy costs and reduce environmental impact.
Heat and mass transfer processes play a key role in chemical technology, providing transformation of matter and energy flows. For increasing their efficiency, various contact devices are used, among which special place is taken by nozzles. Since the moment of creating Rashig’s rings in 1890, engineers are constantly working on improvement of the nozzle designs, adapting them to different conditions of processes and features of interacting substances.
The new nozzle developed at Moscow Polytech is a multi-layer unit of packages of vertical corrugated plates. A key feature of the design is low height of packages and their alternating orientation with a 90 degree rotation relative to the adjacent height packages. Such an arrangement facilitates intensive mixing of streams and improves heat and mass transfer on account of increasing the number of “end effects” – areas of local turbulence of the flow.
“Our new design of a regular nozzle offers the decision capable of increasing the efficiency and cost-effectiveness of a wide spectrum of chemical and technological processes. We hope that this will help to optimize the work of many industrial facilities,” - notes Mikhail Berengarten, Professor of Department “Hardware design and automation of technological productions” and one of the authors of the research that was carried out jointly with a post-graduate Semyon Savenko.
Experimental researches conducted at the column of a diameter of 0,2 meters using the system “air – water” showed impressive results. At the F-factors 1,2 (Pa⁰·⁵) pressure drop in a new nozzle makes up only 250 Pa/m, that is considerably less than traditional nozzles have. The heat transfer coefficient reaches 250 W/ (m2·K), and the coefficient of the mass transfer is about 0.0025 kg/(m2·s). These parameters indicate high efficiency of a new design.
It is especially important that the nozzle is capable of working under high fluid (up to 0,6 m3/h) and gas loads (linear velocity up to 1,2m/h) without reaching the choking mode. This distinguishes it fr om traditional solutions, such as Rashig’s rings, which reach the hydraulic limit under considerably lower loads.
The unique design of the nozzle with technological gaps between the plates considerably reduces the probability of accumulation of solid particles and subsequent formation of carbon deposits or coking. This is making it especially perspective for usage under “hard conditions” of operation, typical for petrochemical industry, wh ere the problem of pollution and coking of contact devices is especially acute.
Low hydraulic resistance of a new nozzle opens wide opportunities for its application in vacuum columns, where this parameter is critically important. In addition, the efficiency of a nozzle allows to reduce the dimensions of column devices while maintaining the efficiency, that may lead to significant savings of space and materials while engineering new facilities.
